The present invention relates to apparatuses for constructing buildings and methods for constructing buildings. More specifically, the present invention applies to construction of various multistory buildings.
One example of a conventional methods for constructing buildings was proposed in JP-A-2-70844. As illustrated in FIG. 1, according to this conventional method, a beam-framework (temporary roof) 1 is assembled on the top of a building 4 which has been already constructed. A plurality of actuators 2 are mounted on the temporary roof 1, so as to extend vertically and downwardly from the temporary roof 1. Extendable rods 3 of the actuators 2, which can extend and retract, are disposed downward from the actuators 2. As shown in the right part of FIG. 1, the distal ends (lower ends) of the rods 3 are temporarily fixed to upper ends of permanent columns 5 of the building 4 by means of nuts and bolts, so that the actuators 2 can become temporary columns for supporting the temporary roof 1.
The temporary roof 1 is then lifted maintaining the horizontal arrangement thereof by means of actuating of the actuators 2 in synchrony. Accordingly, a work space 6, coincident with the space to be occupied by a single story, is provided between the building 4 and the temporary roof 1.
Next, as shown in the left part of FIG. 1, one of the lower ends of the rods 3 is released from the corresponding permanent column 5 and the rod 3 is so retracted that a gap is formed between the upper end of the permanent column 5 and the lower end of the rod 3. A new permanent column 8 is erected in the gap by means of a crane apparatus 7, which lifts the new permanent column 8, and by means of a robot 9, which adjusts the attitude of the permanent column 8. The lower end of the new permanent column 8 is affixed to the upper end of the lower permanent column 5, and the lower end of the rod 3 is temporarily fixed to the upper end of the new permanent column 8. This process is repeated for the remaining rods 3 one by one, so that a plurality of new permanent columns 8 for the new story 6 are erected on the upper ends of the lower permanent columns 5, respectively. In addition, the rods 3 of the actuators 2 are supported by the new permanent columns 8. In this state, flooring and mounting of permanent beams are accomplished for the story 6.
Then, the temporary roof 1 is lifted again maintaining the horizontal arrangement thereof by means of actuating of the actuators 2 in synchrony. After that, the above-described process is repeated, whereby another upper story can be constructed.
However, the above-described method presents the following drawbacks.
That is, it is necessary to provide the large actuators 2 with a very long stroke which is greater than the height of one story of the building. In addition, the number of the actuators 2 used as temporary columns must equal that of the permanent columns 5.
It is troublesome to retract the rods 3 of the actuators 2 one by one and to erect the new permanent columns 8 one by one. In addition, in this case, the working personnel must be move from one column to another column. Furthermore, every actuator 3 needs auxiliary equipment, for example, a fastening robot for the nuts and bolts to fix the rods 3 of the actuators 2 to the permanent columns 5 and 8, a releasing robot to release the rods 3 from the permanent columns 5 and 8, and a welding robot for welding the permanent columns 5 and 8. Hence, the amount of equipment is inevitably large, and thus, the costs for the system are high. In addition, since it is necessary to fasten and release the rods 3 of the actuators 2 to and from the columns 5 and 8, the operation is complicated and thus, the construction costs are high.